Performance / Core Web Vitals — how do they compare?

BigCommerce defaults to good Core Web Vitals on Stencil + their CDN: LCP under 2.5s on average for stock themes, decent INP, low CLS. SaaS hosting is tuned by their infra team — you don’t need a performance specialist.

Magento default Luma is poor on CWV. Magento on Hyvä is excellent: LCP under 1.5s achievable with proper hosting + caching (we’ve hit 1.0s on production stores). But it requires the right setup — Hyvä theme + Varnish + Redis + a competent host + optimized images. Without those, default Magento can hit 5s LCP and tank Lighthouse.

Net: BC is good-by-default. Magento is great-with-effort. If your team can’t / won’t invest in DevOps, BC is the safer CWV bet. With a Hyvä team, Magento beats BC on raw speed.